Regulator for sewing-machines



i l Usrrsn` STA-tras rAUnfrnYiert, or `New soak, n.4 Y.K

Specification forming part of `Lctltrs Patent No. 35,542, dated June10,1862.

i Beit knownthut I, PAULPRYIBIL, ot' the city, county, and Stateof NewYork, havev invented a new and Improved ',lension-Refru- `latorforSewing-lilachiues'; and I dojhereby t declare that the following' isa fullpclear, and '.exact description ofthesame, reference being had totheaccompanyingdrawings,forming part ofthis specitication, in which-v.Figure l represents,` a sectional side elevation .of my invention.`F.ig. 2 is a sectional front`-elevation of thes'aine. Fig. 3 is adetached section of the nut. i

indicate correspondingaparts..` i Y l The object of thisinvention is toincrease the tension ofthe needle-thread of aisewingmachine in the sainemeasure as .thejdiameter ot'the bobbiu in the shuttle' decreases, andcousequentlythe tension ofthe shuttle-thread increases. y i 1The'invention consists in thearrangement ot' a pulley witha long conicalhub, saidpul-y leybeing rotated by the action ot' the needle- Similar"Aletters of reference in both views lhread, in combination with a.screwspindle` acting on the conical hub in such.` a manner that duringthe operation of sewing andcon#y sequent decrease ot` the bobbin-threadin the shuttle'thc pulley, by the action o f the screw, 1 assumes agradual Vdownward motion, thereby bringing thicker andtliicker parts ot'the conical hub opposite the springpad,and calising acorrespondingincrease in `thetcnsion ot' the needle-thread. y j It consistsVfurther,in connecting `the tension -rcgulating pulley with the screw-spindle byan elliliiticalisleeve, which is attached `to a spring, and thefrontportion of which is left smooth, while that portion ofthe smewhichis 'forced by the spring lagainst the screw is i 1 4furnished with a.screw-thread vin such a man- ,nerthat by pullingibaek said spring thenut,

d and with it the pulley, is thrown out of gear with the screw-threadonthe spindle, and can be moved up and down on the same at pleas. ure..i n

` Itconsists, ti nally, in cutting awaythe thread i `in the lower partof said nut, and providing a recessand shoulder in 'thescrewspindle `ini such a `manner that the tension-regulating pulley can be rotatedon thescrew-spindle while theqscrew-threads are out ot` gear, and `hence arenot liable to `become `injured or worn out.l

To enable those skilled in the art to make and use `n iy invention, Iwill proceed to describe it with reference to the drawings;

- ,A represents that portion ot' the frame ot' a sewing-machine whichcarries the pin B,'on which the-spool @rotateswhiclrcarries the-needlethread. This piu is split open and made to produce a certainlriction on the inside ofth'e spool, so that the saine d 'Jes not rotatequite freely, and that it is not liable to drop off when the machine isturned upside down. ,l

The tension'of the needle-thread is produced by a. pulley, D, which isprovided with a long conical huh, E, that is'subjected to the actionofthe spring-padfF. A set-screw, a, serves to regulate hhe'pressurelofthe spring-pad on the hub. The pulley D rotates ou a spindle, G, and theneedlethread is wound round'it once or twice, and as the operation ofsewingproceeds the actionot' the needlethread causes the pulley torotate, and the tension is determined by the amountlot' pressure orfriction exertedhy the spring-pad, which opposes the rotary motion oftheIspring-pulley. Different speeds b c ontlie pulley 'permit the operatorto vary the tension at pleasure. The upper portion ot' the spindle G isprovided with a screw-thread, anda nut, d, which. is secured to aspring, H, rising from the upper surface of the pulley, engages with thescrew-thread on the spindle. This nut is ovulyand the thread 4on thefrontportion-of the salue is cut away,

so that 'by forcing the spring back the thread ot' theinut is thrown outof gear with that on the spindle, and the pulley can now be moved up anddown, quite freelyl When the nut dis lin gear with the spindle, and thepulley I) is vrotated by thegaction ot' the needle-thread in thedirection of the arrow marked upon it in Figs. land 2, said pulleyassumes aigradual downward motion, and the spring-pad ll is therebybrough'tin contact with thicker and thicker portio'ns of theconical h ubE, and consequently the tension ofthe needle-thread increases. Thescrew-thread on the' spindle G and the conical hub E are so arrangedthat the increase ofthe tension of the needle-thread produced by theactioirot' said thread and conical hub is in proportion to the increaseofthe tension of the shuttle- A thread occasioned bythe decrease of thediameter of thebobbin. If it is desired to work he machine withoutchanging the tension of l" Having thus fully described my invention,

the need1e-thread,'the pulley D is moved down upon the spindle, so thatthe n'nt d comes b clow 'the screw-thread on said spindle; and, in

order to save the -screw-thread in the *nut d from being injured byrubbing against the smooth surface of the spindle, a recess, e, isturned into said spindle,l and a shoulder, f, below the recess catchesinto the lower part, g, of the nut d, in which the screw-thread is cntawayentirely, as clearly shown in Fig. 3. By

these means the nut d turns on .theshonlder and the screw-thread in saidnut is notinjured.

This tensionregnlator can be easily attached -foevery sh uttle-machine,and if properly regulated the tension or" the needle and shuttle 'threadis kept perfectly unifnorrn and thework produced by the machine is moreeven and uniform than the work of ordinary sewingmachines, where noaccount is taken of the increasing tension of the 'shuttle-thread.

whatI claim as new, and desire to secure by 'Letters Patent, is-' 1. Thearrangement of the Vfriction-pulley D with the conical lhub E', in4combinationwith the screw-spindle (Bl-A and spring-'pad F, constructedand operating substan'tially-as and for the purpose specified. f

2,. Llhe arrangement ot' the elliptical nut d on the spring H, incombination with thescrews'pindleG'andpulley D., substantiallyas and forthe purpose described.

3. The`1recess e and shonlderf on the screwspindle G, in combinationwith the lower part,

g, of the nut d, as andl for the purpose-set forth.y

PAUL PRYIBIL.;

' Witnesses: EDW. N. HoDGsoN,

JAMEs Lamu., j

